This invention relates to vehicle lifting and towing apparatus and more particularly to apparatus of this type adapted to lift and tow large vehicles such as trucks, buses and the like, the apparatus comprising universally adaptable structure which may be compactly disposed on the rear of a towing vehicle with small rearward extension when stowed and permitting a towed vehicle to be drawn up close to the towing vehicle for proper weight distribution.
Although apparatus for lifting and towing automobiles is well known in the prior art most of this art is not adapted to the lifting and towing of large, bulky and heavy vehicles. Historically, the most common manner of lifting or hoisting and towing disabled vehicles is by attaching a hook on the end of a cable to the bumper or undercarriage of the vehicle and thereafter retracting the cable until it is taut, and then raising the boom over which the cable is carried. This is still the preferred manner utilized for recovery operations, e.g., winching a disabled vehicle out of a ditch or the like. Recently wheel lift apparatus have been developed for lifting and towing vehicles by the wheels. In these devices a pair of wheel supporting frames or troughs are disposed at the end of a boom which is raised to lift the wheels and thus the vehicle. Examples of the various apparatus of this type are disclosed in Nelson U.S. Pat. No. 3,434,608; Peck U.S. Pat. No. 3,951,280; Pigeon U.S. Pat. No. 3,924,763; Petersen U.S. Pat. No. 4,384,817; Cannon, et al U.S. Pat. No. 4,451,193; and Brown U.S. Pat. No. 4,473,334; and in German Auslegeschrift No. 2008523 and German Offenlegungsschrift No. 2821436. In some of these disclosures the apparatus is used in conjunction with wrecker apparatus so that the recovery features are not sacrificed. Other designs, however, are such that they cannot be mounted together with a wrecker on the bed of the towing vehicle and still be capable of having little or no rearward extension when in the stow position.
The known apparatus for lifting and towing large vehicles are merely heftier versions of the automobile lifting and towing apparatus, or are such that the entire disabled vehicle is placed on the bed of the towing vehicle. Thus, they generally either do not have recovery capabilities or the lifting and towing apparatus excessively protrudes beyond the rear of the bed of the vehicle.
The features desirable in lifting and towing apparatus for trucks, buses and other large vehicles (hereinafter cumulatively called "large vehicles") in the stow position include a small above-the-bed extension, a minimal extension beyond the rear of the bed and a significant above-the-ground clearance. Additionally, in the operative position the apparatus should be capable of supporting the towed vehicle closely proximate the rear of the towing vehicle for proper weight distribution and should have variable boom attitude capabilities for loading a vehicle on inclines and the like. Moreover, such apparatus should be flexible enough for use with various vehicles to be towed, but adaptable for use on a multiple of towing vehicles, e.g., vehicles having beds of various distances above the road.